Monolithic Power Systems Inc. MEZS7-2SBOOST CHARGER

Overview

MEZS7-2SBOOST CHARGER from Monolithic Power Systems is a complete 2-cell Li-ion/Li-polymer switching charger and cell-balancing evaluation module built around the MP2639C IC. It delivers 2.5A charge current at 8.4V full-charge voltage with ±0.5% accuracy, integrates JEITA-compliant NTC temperature monitoring, input over-voltage protection (4.49V clamp), and 4-LED fuel gauge indication. It supports USB On-The-Go and USB Type-C discharge-mode 5V back-powering in portable applications such as wireless speakers and gimbals.

For engineers reviewing the MEZS7-2SBOOST CHARGER datasheet, MEZS7-2SBOOST CHARGER pinout, MEZS7-2SBOOST CHARGER application, or MEZS7-2SBOOST CHARGER equivalent, this module provides verified reference design implementation of the MP2639C with pre-configured 3A input current limit, 2.5A charge current, and integrated balancing-enabling rapid validation of dual-cell battery charging, thermal safety, and USB-compliant power path management.

Technical Context

The MEZS7-2SBOOST CHARGER implements a boost-based switching charger architecture using the MP2639C controller with integrated high-side and low-side FETs. It operates in constant-current/constant-voltage (CC/CV) mode with programmable input current limit (3A), input voltage regulation (4.49V), and charge-full threshold (8.4V).

Cell balancing is achieved via passive resistor-based dissipation across each cell during charge termination, synchronized with the MP2639C's BAL pin control logic. The module includes dedicated NTC interface (RNTC1/RNTC2), LED drivers for state-of-charge indication, and thermal shutdown with regulation loop active above 125°C.

Key Specifications

Availability

MEZS7-2SBOOST CHARGER is available at Aetrix Electronics and suitable for wireless speaker development, gimbal power systems, e-cigarette battery management, and battery backup modules requiring stable component supply, pre-validated safety features, and USB-compliant discharge capability.

Supply support for MEZS7-2SBOOST CHARGER includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance power management ICs, including battery chargers, DC/DC converters, and motor drivers for portable, industrial, and automotive applications.

The MEZS7-2SBOOST CHARGER belongs to MPS's solution module product line-designed to accelerate customer evaluation of key ICs like the MP2639C by delivering fully assembled, tested, and documented reference designs with production-ready layout and BOM.

FAQ

What is the primary function of the MEZS7-2SBOOST CHARGER module?

This module is a ready-to-use evaluation platform for the MP2639C battery management IC. It performs regulated 2-cell Li-ion charging with integrated cell balancing, JEITA temperature monitoring, input protection, and 4-LED fuel gauge indication-all on a compact 3cm × 2.8cm PCB. It is not a standalone IC but a functional hardware reference design.

Does the module support reverse power delivery to a USB host?

Yes. In discharge mode, the MEZS7-2SBOOST CHARGER can deliver a regulated 5V output back to the USB port, compliant with USB On-The-Go and USB Type-C specifications. This enables bidirectional power flow when the battery is charged and the USB port is connected to a host device.

How is cell balancing implemented on this board?

Passive cell balancing is implemented using discrete resistors controlled by the MP2639C's BAL pin. During charge termination, the IC activates balancing paths across each cell to equalize voltages. The schematic confirms two 10kΩ resistors (R4, R18) tied to the MID node and BAL pin, enabling ~50mA per cell dissipation at 4.2V.

What are the critical external components required to operate the module?

No external components are required for basic operation. The module includes all necessary passives: input/output capacitors (C1–C10), inductor (L1), Schottky diode (D1), MOSFET (M1), NTC network (RNTC1/RNTC2), and LED drivers. Only a 2S battery pack and 5V USB source are needed to begin evaluation.

Can the charge parameters be reconfigured, and how?

Yes. Charge current (ICHG), input current limit (IIN_LIM), and input voltage clamp (VIN_CLAMP) are resistor-programmable. For example, replacing RISET (86.6kΩ) adjusts charge current; changing RILIM (79kΩ) modifies input current limit; and tuning R3/R4 alters the 4.49V clamp threshold per Equation (3) in the quick-start guide.

Is the module RoHS-compliant and lead-free?

Yes. All components on the MEZS7-2SBOOST CHARGER meet RoHS requirements and are lead-free and halogen-free, consistent with MPS's green policy. The PCB uses ENIG surface finish, and the MP2639CGR IC is qualified to JEDEC MSL-3 standards.